Why are assets not refreshed on Assets page

Hi,

I've deleted and also created new assets, but when I click on "Asset", the left hand side "Filter your search" area is not updated properly.  e.g. Before I did anything, I had 12 assets in RAM.  I deleted 6 of them and waited and waited.  When I clicked on "Assets", in the "Filter your search" area, I still see RAM saying I have 12 assets.  I clicked on it and still could see the list of 12 assets.  I clicked on any one of those which I deleted and RAM will tell me it doesn't exist anymore (which is true since I deleted it).  But why is the page not refreshed showing only the 6 assets which remain?

thanks